The project is designed to understand the way nutrients such as hexoses and amino acids affect hunger. Duodenal and hepatic-portal infusions of nutrients with simultaneous or parallel blood sampling for pancreatic and gut hormones and metabolites are proposed. Parallel measures of metabolic flux in liver and fat cells will also be done. The role of the lateral hypothalamic area in affecting meal patterns and metaoblism will also be explored. In particular the effects of lesions and knife-cuts on lipid mobilization will be investigated. Finaaly, we plan to investigate by histochemical and microelectrode technique the interaction of visceral, gustatory anc central receptors involved in carbohydrate, salt and water metabolism. The objective is to gain a fuller understanding of the basic physiological signals initiating and terminating autonomic and behavioral mechanisms of humger and thirst.